The parent application disclosed a multiple-fold windproof umbrella having valves openable for escaping strong wind blowing into the umbrella cloths and automatically restored for closing the opening between the upper and lower cloths after the escape of wind. A net member 3a is provided to secure the lower cloth towards the central shaft for a uniform stress distribution on the net member and the lower cloth. Such a net member will increase the installation complexity since the net member 3a should pass through every base portion 41 of each control valve 4, thereby increasing the production cost of the umbrella.
If the net member 3a is eliminated as shown in FIG. 8 as attached in this application, the lower umbrella cloth 3 may be sagged (S) when folding the umbrella, thereby causing tangling of the lower and the upper cloths 3, 5 and obstructing a smooth unfolding and folding operation of the umbrella.
The present inventor has found the drawbacks of the parent application and invented the present multiple-fold windproof umbrella for preventing sagging of umbrella cloth.